1. Field of Invention
The present invention relates to a liquid crystal display device and an electronic apparatus. More specifically, the invention relates to obtaining a display having a high contrast and a wide viewing angle in a transflective liquid crystal display device in which display is performed in both a reflection mode and a transmission mode.
2. Description of Related Art
A related art liquid crystal display device includes a transflective liquid crystal display device providing display that is visible using external light, similarly to the reflective liquid crystal display device, in a bright place. The transflective liquid crystal display provides display uses a backlight, similarly to the transmissive liquid crystal display device, in a dark place. Such a related art transflective liquid crystal display device includes a liquid crystal display device in which a liquid crystal layer is interposed between an upper substrate and a lower substrate, a reflective film obtained by forming window portions to transmit light in a metal film made of aluminum, etc., is provided on the inner surface of a lower substrate, and the reflective film is then allowed to serve as a transflective plate. In this case, in the reflection mode, the external light incident from the upper substrate side passes through the liquid crystal layer, is reflected from the reflective film at the inner surface of the lower substrate, passes through the liquid crystal layer again, and is emitted from the upper substrate side, thereby contributing to the display. On the other hand, in the transmission mode, light from a backlight incident from the lower substrate side passes through the liquid crystal layer from the window portions of the reflective film and is externally emitted from the upper substrate side, thereby contributing to the display. Therefore, in an area in which the reflective film is formed, the areas in which the window portions are formed become the transmissive display areas, and the areas other than transmissive display areas become the reflective display areas.
However, the related art transflective liquid crystal display device is subject to a problem in that the viewing angle in the transmissive display is narrow. This is because a transflective plate is provided at an inner surface of a liquid crystal cell so as not to generate parallax, and thus there is a restriction in that the reflective display is performed using only one polarizer provided in an observer side. Therefore, the degree of freedom in the optical design is small. Therefore, in order to address or solve the above, a related art liquid crystal display device uses a vertically aligned liquid crystal, which is disclosed in “Development of transflective LCD for high contrast and wide viewing angle by using homeotropic alignment”, M. Jisaki et al., Asia Display/IDW'01, pp. 133–136 (2001), (hereinafter “Jisaki et al.”). Three features thereof are as follows:
(1) A “VA (Vertical Alignment) mode” is employed, in which a liquid crystal having a negative dielectric anisotropy is aligned vertically at the substrate and then it is slanted by applying a voltage.
(2) A “multi gap structure” is employed, in which the thickness of the liquid crystal layer in the transmissive display areas and the reflective display areas are different each other (for this feature, see, for example, Japanese Unexamined Patent Application Publication No. 11-242226).
(3) The transmissive display areas are formed as regular octagons, and projections are provided at the centers of the transmissive display areas on the counter substrate such that the liquid crystal molecules are slanted in eight directions in those areas. That is, a so-called “alignment division structure” is employed.